This invention relates to torque wrenches, and in particular to a torque wrench with an easy set and easy read dial on the rearmost end of the handle.
Due to increasing use of lighter and softer metal, alloy, and even plastic components, torque wrenches are being used more and more to measure the amount of tightening force (or torque) applied to corresponding fasteners. Precision tightening of bolts is necessary on automobiles, power mowers, outboard motors, household appliances, and many other devices. Too much tightening force can stretch the fastener past the point from which it can snap back into original shape after being stretched, making it unfit for further use and possibly warping or twisting the component which is being tightened down. Too little tension reduces the fastener's ability as a clamping device.
In the past, two types of torque wrenches have been available to the general public; i.e., the ratchet type and the lever type. The ratchet (micrometer) type is far more accurate and is used where precise measurements are necessary. However, conventional ratchet type torque wrenches also have their drawbacks. Obviously, the lever type torque wrench is inaccurate and does not limit the amount of torque being applied, but only measures the amount of torque being applied. Conventional ratchet type torques wrenches as shown in FIG. 5 of the present drawings, on the other hand, are accurate but are not as convenient to use, for several reasons:
(1) the pitch of the inner threading of a micrometer type ratchet torque wrench is small, so that it takes about 10 turns of the micrometer handle (D) to turn form the lowest torque setting to the highest torque setting;
(2) the micrometer handle (D) is movable along the shank (C) of the wrench, thereby causing slight variations and inaccuracies in the amount of torque actually applied to the fastener (since torque is basically equal to force times distance); and
(3) a locking device (E) is required in order to stabilize the setting on the micrometer handle (D).
It is the purpose of this present invention, therefore, to mitigate and/or obviate the above-mentioned drawbacks in the manner set forth in the detailed description of the preferred embodiment.